Blade housing for a lawn mower



FIG. 1 is a perspective view of a blade housing for a lawn mower embodying my new design as seen from above and to one side thereof;

FIG. 2 is a side elevational view thereof, the opposite side being the same except that it is not slotted but rather continuous;

FIG. 3 is a top plan view thereof; and

FIG. 4 is a bottom plan view thereof. 

The ornamental design for a blade housing for a lawn mower, substantially shown and described. 